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Hejá,tko, Jan,Ryu, Hojin,Kim, Gyung-Tae,Dobesová,, Romana,Choi, Sunhwa,Choi, Sang Mi,Soucek, Premysl,Horá,k, Jakub,Peká,rová,, Blanka,Palme, Klaus,Brzobohaty, Bretislav,H American Society of Plant Physiologists 2009 The Plant cell Vol.21 No.7
<P>The development and activity of the procambium and cambium, which ensure vascular tissue formation, is critical for overall plant architecture and growth. However, little is known about the molecular factors affecting the activity of vascular meristems and vascular tissue formation. Here, we show that the His kinase CYTOKININ-INDEPENDENT1 (CKI1) and the cytokinin receptors ARABIDOPSIS HISTIDINE KINASE2 (AHK2) and AHK3 are important regulators of vascular tissue development in Arabidopsis thaliana shoots. Genetic modifications of CKI1 activity in Arabidopsis cause dysfunction of the two-component signaling pathway and defects in procambial cell maintenance. CKI1 overexpression in protoplasts leads to cytokinin-independent activation of the two-component phosphorelay, and intracellular domains are responsible for the cytokinin-independent activity of CKI1. CKI1 expression is observed in vascular tissues of inflorescence stems, and CKI1 forms homodimers both in vitro and in planta. Loss-of-function ahk2 and ahk3 mutants and plants with reduced levels of endogenous cytokinins show defects in procambium proliferation and an absence of secondary growth. CKI1 overexpression partially rescues ahk2 ahk3 phenotypes in vascular tissue, while the negative mutation CKI1H405Q further accentuates mutant phenotypes. These results indicate that the cytokinin-independent activity of CKI1 and cytokinin-induced AHK2 and AHK3 are important for vascular bundle formation in Arabidopsis.</P>
Ferná,ndez, Ximena,Gim, Hansung B.,Gorkom, J. H. van,Yun, Min S.,Momjian, Emmanuel,Popping, Attila,Chomiuk, Laura,Hess, Kelley M.,Hunt, Lucas,Kreckel, Kathryn,Lucero, Danielle,Maddox, Natasha,Oo American Astronomical Society 2016 ASTROPHYSICAL JOURNAL LETTERS - Vol.824 No.1
<P>Our current understanding of galaxy evolution still has many uncertainties associated with the details of the accretion, processing, and removal of gas across cosmic time. The next generation of radio telescopes will image the neutral hydrogen (H I) in galaxies over large volumes at high redshifts, which will provide key insights into these processes. We are conducting the COSMOS H I Large Extragalactic Survey (CHILES) with the Karl G. Jansky Very Large Array, which is the first survey to simultaneously observe H I from z = 0 to z similar to 0.5. Here, we report the highest redshift H I 21 cm detection in emission to date of the luminous infrared galaxy COSMOS J100054.83+023126.2 at z = 0.376 with the first 178 hr of CHILES data. The total H I mass is (2.9 +/- 1.0) x 10(10) M-circle dot and the spatial distribution is asymmetric and extends beyond the galaxy. While optically the galaxy looks undisturbed, the H I distribution suggests an interaction with a candidate companion. In addition, we present follow-up Large Millimeter Telescope CO observations that show it is rich in molecular hydrogen, with a range of possible masses of (1.8-9.9) x 10(10) M-circle dot. This is the first study of the H I and CO in emission for a single galaxy beyond z similar to 0.2.</P>
Tuning microcavities in thermally rearranged polymer membranes for CO<sub>2</sub> capture
Han, S. H.,Kwon, H. J.,Kim, K. Y.,Seong, J. G.,Park, C. H.,Kim, S.,Doherty, C. M.,Thornton, A. W.,Hill, A. J.,Lozano, Á,. E.,Berchtold, K. A.,Lee, Y. M. The Royal Society of Chemistry 2012 Physical Chemistry Chemical Physics Vol.14 No.13
<P>Microporous materials have a great importance in catalysis, delivery, storage and separation in terms of their performance and efficiency. Most microporous materials are comprised of inorganic frameworks, while thermally rearranged (TR) polymers are a microporous organic polymer which is tuned to optimize the cavity sizes and distribution for difficult separation applications. The sub-nano sized microcavities are controlled by <I>in situ</I> thermal treatment conditions which have been investigated by positron annihilation lifetime spectroscopy (PALS). The size and relative number of cavities increased from room temperature to 230 °C resulting in improvements in both permeabilities and selectivities for H<SUB>2</SUB>/CO<SUB>2</SUB> separation due to the significant increase of gas diffusion and decrease of CO<SUB>2</SUB> solubility. The highest performance of the well-tuned TR-polymer membrane was 206 Barrer for H<SUB>2</SUB> permeability and 6.2 of H<SUB>2</SUB>/CO<SUB>2</SUB> selectivity, exceeding the polymeric upper bound for gas separation membranes.</P> <P>Graphic Abstract</P><P>Thermally rearranged polybenzoxazoles with tuned cavities for hydrogen purification and carbon dioxide separation even at high temperature were developed to apply for a syn gas separation. <IMG SRC='http://pubs.rsc.org/services/images/RSCpubs.ePlatform.Service.FreeContent.ImageService.svc/ImageService/image/GA?id=c2cp23729f'> </P>
THE UNAM-KIAS CATALOG OF ISOLATED GALAXIES
Herná,ndez-Toledo, H. M.,Vá,zquez-Mata, J. A.,Martí,nez-Vá,zquez, L. A.,Choi, Yun-Young,Park, Changbom American Institute of Physics 2010 The Astronomical journal Vol.139 No.6
<P>A new catalog of isolated galaxies from the Sloan Digital Sky Survey Data Release 5 (SDSS DR5) is presented. A total of 1520 isolated galaxies were found in 1.4 sr of sky. The selection criteria in this UNAM-KIAS catalog are a variation on the criteria developed by Karachentseva, including full redshift information. Through an image processing pipeline that takes advantage of the high-resolution (~0<img entity='farcs' SRC='http://ej.iop.org/icons/Entities/farcs.gif' ALT='farcs' ALIGN='BOTTOM' />4 pixel<SUP>–1</SUP>) and high dynamic range of the SDSS images, a uniform g-band morphological classification for all these galaxies is presented. We identify 80% (Sa-Sm) spirals (50% later than Sbc types) on one hand, and a scarce population of early-type E (6.5%) and S0 (8%) galaxies amounting to 14.5% on the other hand. This magnitude-limited catalog is ~80% complete at 16.5, 15.6, 15.2, 14.6, and 14.4 mag in the ugriz bands, respectively. Some representative physical properties including SDSS magnitudes and color distributions, color-color diagrams, absolute magnitude-color, and concentration-color diagrams as a function of morphological type are presented. The UNAM-KIAS Morphological Atlas is also released along with this paper. For each galaxy of a type later than Sa, a mosaic is presented that includes (1) a g-band logarithmic image, (2) a g-band filtered-enhanced image where a Gaussian kernel of various sizes was applied, and (3) a red giant branch color image from the SDSS database. For E/S0/Sa galaxies, in addition to the images in (1), (2), and (3), plots of r-band surface brightness and geometric profiles (ellipticity ε, position angle PA, and A<SUB>4</SUB>/B<SUB>4</SUB> coefficients of the Fourier series expansions of deviations of a pure ellipse) are provided. The size of the sample, the redshift completeness, the availability of high-quality multicolor photometric data and detailed morphological and spectroscopic information make the UNAM-KIAS catalog of isolated galaxies a suitable sample to address important issues such as (1) comparative studies of environmental effects, (2) constraining the currently competing scenarios of galaxy formation and evolution, (3) the nature and evolution of elliptical and spiral galaxies in the field, (4) the spectral properties of a statistically significant number of isolated galaxies and their evolution as a function of redshift, and (5) the fraction of active galactic nuclei in isolated environments, among other important topics. The optimization and estimation of new structural parameters as well as important information to complement existing ones in other wavelengths is being carried out.</P>
Periá,ñ,ez, R.,Bezhenar, R.,Brovchenko, I.,Duffa, C.,Iosjpe, M.,Jung, K.T.,Kobayashi, T.,Lamego, F.,Maderich, V.,Min, B.I.,Nies, H.,Osvath, I.,Outola, I.,Psaltaki, M.,Suh, K.S.,de With, G. Elsevier 2016 Science of the Total Environment Vol.569 No.-
<P><B>Abstract</B></P> <P>State-of-the art dispersion models were applied to simulate <SUP>137</SUP>Cs dispersion from Chernobyl nuclear power plant disaster fallout in the Baltic Sea and from Fukushima Daiichi nuclear plant releases in the Pacific Ocean after the 2011 tsunami. Models were of different nature, from box to full three-dimensional models, and included water/sediment interactions. Agreement between models was very good in the Baltic. In the case of Fukushima, results from models could be considered to be in acceptable agreement only after a model harmonization process consisting of using exactly the same forcing (water circulation and parameters) in all models. It was found that the dynamics of the considered system (magnitude and variability of currents) was essential in obtaining a good agreement between models. The difficulties in developing operative models for decision-making support in these dynamic environments were highlighted. Three stages which should be considered after an emergency, each of them requiring specific modelling approaches, have been defined. They are the emergency, the post-emergency and the long-term phases.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Models applied to simulate <SUP>137</SUP>Cs marine dispersion after nuclear accidents. </LI> <LI> Not good agreement initially found in highly dynamic environments. </LI> <LI> Difficulties in developing models for decision making after emergencies highlighted. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>
Observing the onset of outflow collimation in a massive protostar
Carrasco-Gonzá,lez, C.,Torrelles, J. M.,Cantó,, J.,Curiel, S.,Surcis, G.,Vlemmings, W. H. T.,van Langevelde, H. J.,Goddi, C.,Anglada, G.,Kim, S.-W.,Kim, J.-S.,Gó,mez, J. F. American Association for the Advancement of Scienc 2015 Science Vol.348 No.6230
<P><B>Young stars grow up and narrow their focus</B></P><P>Stars are thought to grow by gathering spirals of material from a disk. If this is the case, to balance angular momentum, gas should flow out rapidly along the disk's rotation axis. Carrasco-Gonzalez <I>et al.</I> now seem to have glimpsed the “before” and “after” stages of the onset of such an outflow, over the course of just 18 years (see the Perspective by Hoare). Radio monitoring of the massive protostar W75N(B)-VLA2 reveals a transition from a spherical wind to a collimated one, giving critical insight into what happens as a massive star forms.</P><P><I>Science</I>, this issue p. 114; see also p. 44</P><P>The current paradigm of star formation through accretion disks, and magnetohydrodynamically driven gas ejections, predicts the development of collimated outflows, rather than expansion without any preferential direction. We present radio continuum observations of the massive protostar W75N(B)-VLA 2, showing that it is a thermal, collimated ionized wind and that it has evolved in 18 years from a compact source into an elongated one. This is consistent with the evolution of the associated expanding water-vapor maser shell, which changed from a nearly circular morphology, tracing an almost isotropic outflow, to an elliptical one outlining collimated motions. We model this behavior in terms of an episodic, short-lived, originally isotropic ionized wind whose morphology evolves as it moves within a toroidal density stratification.</P>
CARMA LARGE AREA STAR FORMATION SURVEY: DENSE GAS IN THE YOUNG L1451 REGION OF PERSEUS
Storm, Shaye,Mundy, Lee G.,Lee, Katherine I.,Ferná,ndez-Ló,pez, Manuel,Looney, Leslie W.,Teuben, Peter,Arce, Hé,ctor G.,Rosolowsky, Erik W.,Meisner, Aaron M.,Isella, Andrea,Kauffmann American Astronomical Society 2016 The Astrophysical journal Vol.830 No.2
<P>We present a 3 mm spectral line and continuum survey of L1451 in the Perseus Molecular Cloud. These observations are from the CARMA Large Area Star Formation Survey (CLASSy), which also imaged Barnard. 1, NGC 1333, Serpens Main, and Serpens South. L1451 is the survey region with the lowest level of star formation activity-it contains no confirmed protostars. HCO+, HCN, and N2H+ (J = 1 -> 0). are all detected throughout the region, with HCO+ being the most spatially widespread, and molecular emission seen toward 90% of the area above N(H-2) column densities of 1.9 x 10(21) cm(-2). HCO+ has the broadest velocity dispersion, near 0.3 km s(-1) on average, compared with similar to 0.15 km s(-1) for the other molecules, thus representing a range of subsonic to supersonic gas motions. Our non-binary dendrogram analysis reveals that the dense gas traced by each molecule has a similar hierarchical structure, and that gas surrounding the candidate first hydrostatic core (FHSC), L1451-mm, and other previously detected single-dish continuum clumps has similar hierarchical structure; this suggests that different subregions of L1451 are fragmenting on the pathway to forming young stars. We determined that the three-dimensional morphology of the largest detectable dense-gas structures was relatively ellipsoidal compared with other CLASSy regions, which appeared more flattened at the largest scales. A virial analysis shows that the most centrally condensed dust structures are likely unstable against collapse. Additionally, we identify a new spherical, centrally condensed N2H+ feature that could be a new FHSC candidate. The overall results suggest that L1451 is a young region starting to form its generation of stars within turbulent, hierarchical structures.</P>
Multisite campaign on the open cluster M67 – III. δ Scuti pulsations in the blue stragglers
Bruntt, H.,Stello, D.,Suá,rez, J. C.,Arentoft, T.,Bedding, T. R.,Bouzid, M. Y.,Csubry, Z.,Dall, T. H.,Dind, Z. E.,Frandsen, S.,Gilliland, R. L.,Jacob, A. P.,Jensen, H. R.,Kang, Y. B.,Kim, S.-L. Blackwell Publishing Ltd 2007 MONTHLY NOTICES- ROYAL ASTRONOMICAL SOCIETY Vol.378 No.4
<P>ABSTRACT</P><P>We have made an asteroseismic analysis of the variable blue stragglers in the open cluster M67. The data set consists of photometric time-series from eight sites using nine 0.6–2.1 m telescopes with a time-baseline of 43 d. In two stars, EW Cnc and EX Cnc, we detect the highest number of frequencies (41 and 26) detected in δ Scuti stars belonging to a stellar cluster, and EW Cnc has the second highest number of frequencies detected in any δ Scuti star. We have computed a grid of pulsation models that take the effects of rotation into account. The distribution of observed and theoretical frequencies shows that in a wide frequency range a significant fraction of the radial and non-radial low-degree modes are excited to detectable amplitudes. Despite the large number of observed frequencies we cannot constrain the fundamental parameters of the stars. To make progress we need to identify the degrees of some of the modes from either multicolour photometry or spectroscopy.</P>
CHILES: H i morphology and galaxy environment at <i>z</i> = 0.12 and <i>z</i> = 0.17
Hess, Kelley M,Luber, Nicholas M,Ferná,ndez, Ximena,Gim, Hansung B,van Gorkom, J H,Momjian, Emmanuel,Gross, Julia,Meyer, Martin,Popping, Attila,Davies, Luke J M,Hunt, Lucas,Kreckel, Kathryn,Luce Oxford University Press 2019 MONTHLY NOTICES- ROYAL ASTRONOMICAL SOCIETY Vol.484 No.2